This entry represents the Walker B domain of RAD50 from eukaryotes and the prokaryotic homologue SbcCD complex subunit C. RAD50-ATPase forms a complex with Mre11-nuclease that detects and processes diverse and obstructed DNA ends. This domain is separated of the Walker A domain by a long coiled-coil domain and forms the nucleotide-binding domain (NBD) when the coiled coils fold back on themselves and bring together Walker A and B domains [1,2,3,4]. Two RAD50-NBDs forms heterotetramers with a Mre11 nuclease dimer that assemble as catalytic head module that binds and cleaves DNA in an ATP-dependent reaction. Through secondary structural analysis, it has been suggested that there is a wide structural conservation in the Rad50/SMC protein family as seen in structural similarities between RAD50's hook and ABC-ATPase MukB's elbow region [4]. [1]. 26896444. Structural mechanism of ATP-dependent DNA binding and DNA end bridging by eukaryotic Rad50. Seifert FU, Lammens K, Stoehr G, Kessler B, Hopfner KP;. EMBO J. 2016;35:759-772. [2]. 21892167. The Rad50 coiled-coil domain is indispensable for Mre11 complex functions. Hohl M, Kwon Y, Galvan SM, Xue X, Tous C, Aguilera A, Sung P, Petrini JH;. Nat Struct Mol Biol. 2011;18:1124-1131. [3]. 28134932. Eukaryotic Rad50 functions as a rod-shaped dimer. Park YB, Hohl M, Padjasek M, Jeong E, Jin KS, Krezel A, Petrini JH, Cho Y;. Nat Struct Mol Biol. 2017;24:248-257. [4]. 31492634. Mechanism of DNA End Sensing and Processing by the Mre11-Rad50 Complex. Kashammer L, Saathoff JH, Lammens K, Gut F, Bartho J, Alt A, Kessler B, Hopfner KP;. Mol Cell. 2019;76:382-394. (from Pfam)
- Date:
- 2025-01-31